Hayward H400FDN temperature sensor

[JamesW]

Inadequate gas supply. Piping too small.
This last is what he thinks is the problem. Back at the house, there's a small-diameter pipe connecting the "house" stuff to the pool stuff.
Also - the earthquake valve is too small. If that's true, I have a bone to pick with my pool builder. If their inadequate installation causes
a 20-year heater to last only 2-3 years, I think they owe me a fix.

Your expert should be able to give you a technical analysis of the gas supply with things like pressures and pressure drop estimates for everything.

Can you show all gas supply components including things like Meter, Regulators, Piping etc. with all model numbers, sizes, lengths etc?

 

[ajw22]

* Inadequate gas supply. Piping too small.
This last is what he thinks is the problem. Back at the house, there's a small-diameter pipe connecting the "house" stuff to the pool stuff.

Show us pictures of your gas meter, gas meter data plates, and all the visible gas pipes to the heater.

What is the distance from the gas meter to the pool heater?

What is the size of the gas pipes?

https://hayward.com/media/akeneo_connector/asset_files/U/n/Universal_H_Series_Install_Manual_Bilingual_1f1f.pdf

Also - the earthquake valve is too small. If that's true, I have a bone to pick with my pool builder. If their inadequate installation causes a 20-year heater to last only 2-3 years, I think they owe me a fix.

What is an earthquake valve?

 

[JamesW]

Earthquake shut-off valves are designed to close in the event of a severe earthquake.

Threaded Earthquake Valves - Pacific Seismic Products

Earthquake shut-off valves sizes 3/4" to 4" NPT threaded. Many sizes in stock. Quick turnaround. Earthquake shut-off valves are designed to close in the event of a severe earthquake. Secure the safety of your home, office building or industrial operation with the addition of an earthquake...

mcsmeters.com

The Hayward Fault:Hazards

UC Berkeley Seismological Lab

earthquakes.berkeley.edu

 

[ajw22]

Earthquake shut-off valves are designed to close in the event of a severe earthquake.

On a gas line?

 

[JamesW]

On a gas line?

Yes.

The Bay Area is home to many active faults that can erupt at anytime.

Scientists have studied the faults extensively and determined that the Hayward is probably the most dangerous.

It has a 31.7% chance of rupturing in a 6.7 magnitude earthquake or greater before 2036, and the Bay Area has a 63% chance of having at least a magnitude 6.7 earthquake in the same time period.

Therefore, it is essential that every citizen in the area take a few moments and make sure they know what the potential hazards are, and what they can do to prepare.

Hazards

Major active faults such as the Hayward Fault are associated with many hazards.

The most obvious hazard is that of large earthquakes, which induce ground shaking over a large area that can cause heavy objects to fall and windows to shatter, and can cause structural damage to buildings and bridges.

Strong shaking and fault rupture can also lead to many other problems, including landsliding, liquefaction, fires, disrupted transportation routes, broken water and gas pipes, downed electrical and phone lines, and many other dangerous conditions.

 

[JamesW]

How Earthquake Shut-Off Valves Work.

An earthquake shut off valve, also known as a seismic valve, is an automatic safety feature that turns off gas flow to a home or commercial property during an earthquake.

The valve is installed on the gas meter of your property and turns off the gas when it registers an earthquake above 5.4 to prevent explosions and fires that result from broken gas lines during earthquakes.

About Earthquake and Excess-flow Valves | SoCalGas

Learn how to purchase install and use earthquake shut-off and excess-flow valves.

www.socalgas.com

City Clamps Down on Shut-Off Valve Installation

Quake safety: Council gives preliminary OK to requiring the gas devices before escrow closes. Homeowners currently have a year to comply.

www.latimes.com

Earthquake Shut-Off Valves in Los Angeles, CA | Red Lilly Plumbing

Keep your home safe from dangerous broken gas lines with Red Lilly Plumbing's emergency earthquake shut-off valve services in Los Angeles, California. Contact us to get your seismic shut-off valve installed!

www.redlillyplumbing.com

 

[jerryk1234]

OK, I ordered another H400FDN. It should be a simple drop-in replacement. There was a listing on Amazon selling them really cheap - about $900 less than everybody else. But it's a new vendor, no feedback, not a pool specialty company. All sorts of ways that could go wrong. I ordered it from Inyopools. I *also* ordered an acid injector system from Hanna Instruments. So the pool will always be 7.5.
I contacted my plumber to see about upgrading the gas flow.
The pool repair guy says that if *he* installs the heater, then Hayward will honor the warranty. But he wants $2000 for that.

Another thing he mentioned - a pool heater can be damaged by excessive water flow. I run the pump at 40% when it's gas heating.
But I run it at 65% for the solar - because the solar array is up the hill. There is a valve that directs water either to the heater input or up
the hill. But the *return* from the solar array goes to the heater input.

There is a bypass built into the heater manifold. If that fails, I guess it pumps water through the heater all the time. The pool guy said that at least one of his customers replaces that bypass every year. How does that work, anyway? Is it electrical?

 

[ajw22]

Another thing he mentioned - a pool heater can be damaged by excessive water flow. I run the pump at 40% when it's gas heating.
But I run it at 65% for the solar - because the solar array is up the hill. There is a valve that directs water either to the heater input or up
the hill. But the *return* from the solar array goes to the heater input.

Your pool buy is starting to BS you. Yes, there is a maximum flow rate for the heater.

But, your pump can not push 125 GPM through your pipes, and filter. Your pump at maximum RPM probably cannot hot 80 GPM.

There is a bypass built into the heater manifold. If that fails, I guess it pumps water through the heater all the time. The pool guy said that at least one of his customers replaces that bypass every year. How does that work, anyway? Is it electrical?

The internal bypass valve works with a spring. Even if it fails your plumbing cannot exceed the maximum flow rate.

 

[ajw22]

Do you run your heater in the winter with low water temperatures? If so, corrosive condensation could be your problem.

Heater Condensation - Further Reading

www.troublefreepool.com

 

[jerryk1234]

I just got off the phone with Hayward tech support. He said that the leading reason for returned heaters is just water chemistry. Strangely
enough, even the warranty mentions it. Specifically, PH above 7.8. Our water constantly trends alkaline... When the PH goes up, it increases
the tendency for calcium to coat the pipes. I have ordered an acid dosing system. Also, he verified that if I stick a manometer on the input and it's within spec while the heater is running, then the gas piping is OK.

AND he verified that the warranty does NOT require "installation by a pool professional". You just have to do it right.

Another point of failure: there is a check valve at the heater output. It's important. It needs to work.

 

[jerryk1234]

Do you run your heater in the winter with low water temperatures? If so, corrosive condensation could be your problem.

Heater Condensation - Further Reading

www.troublefreepool.com

We do run year round. We keep the pool at 84 degrees. The heater only runs in the fall & winter; in the spring & summer, the solar system keeps up.

 

[ajw22]

Strangely
enough, even the warranty mentions it. Specifically, PH above 7.8. Our water constantly trends alkaline... When the PH goes up, it increases
the tendency for calcium to coat the pipes.

Yes, high pH will damage a heat exchanger but not in the way yours was damaged.

High pH causes calcium scale to form in the heat exchanger tubes, clogging them. The scale does not cause leaks.

In fact, a calcium coating is needed on the copper tubes to protect them from the chemicals. When the pH is low, the calcium scale is stripped off the copper, allowing the chemicals to wear it.

Any pH in the 7s is fine for the heater. Running the heater for extended periods with a pH above 8.2 and high TA causes a high CSI and the calcium scale to build up.

Heater Maintenance - Further Reading

www.troublefreepool.com

Heater Scaling and Failed Thermoregulator: Jandy Jxi 400 NG with VF

Hello everyone. Have had a Jandy JXi 400NG with versaflo installed for about a year. Recently had very loud banging/knocking occurring when the gas heater ignited. My PB has come by to service the heater and said that 1) the thermoregulator had failed and 2) there was a large amount of scale...

www.troublefreepool.com

Flakes/Scale Buildup in Heat Exchanger

Hello, I continue to struggle with flakes/scale buildup in my heat exchanger (I posted in 2018 on this). Last spring I had to ream scale out of my heat exchanger in order to restore flow. I also set up controls so the heater starts a half hour after the pump is running and shuts off a half...

www.troublefreepool.com

 

[jerryk1234]

OK. New heater received, installed & working. It was a pain getting it up to the equipment pad - one flight of steps, and the thing weighs 135 pounds. I accomplished it with the help of a young neighbor with a good back - and a stair-climbing dolly.
I got the old one down myself. Just took it apart till it was light enough. Removing the heat exchanger got a lot of weight off it.

A pool repair guy said he could install it - for $2000. Nah, I don't think so. I talked to tech support at Hayward and asked - what about the warranty? Does it have to be installed by a pool professional( which is what the pool repair guy said )? Nope, it just needs to be done right.

While I was at it, I cleaned the pool filter cartridges, took apart the sacrificial anode pod and tidied that up, and took out the guts of the heater output check valve. I need a new one of those. The rubberized sealing strip around the edge of the flap has mostly disappeared. On order. I also did a inspection & cleaning of the salt cell.
There is calcium grit everywhere. But not enough of it to clog anything. I think I'll cut the old heat exchanger apart for a post-mortem.

I have a Hanna acid injection system on order. Not sure what I'm going to keep the acid in. If all else fails, I can just customize
the cap of the acid jugs from the store - a hole for a hose, and another hole for air. And put the jug inside a bucket in case of leaks, and to protect it from UV. And when it runs out, just pop the cap on another jug.

I plan to stick a manometer on the gas valve to check the input pressure. It's supposed to be between 11.5 & 4.5 - I think "inches of water". Needs to be done while the heater is operating, to see if the pressure drop in the pipe run is excessive.

I bought the new heater on a credit card that doubles the warranty...

 

[jerryk1234]

Life is full of challenges... I went up with my digital manometer to measure the inlet pressure at the heater - no luck. The gas valve does not seem to have an intake manometer port. Whups, I found it. It's hidden next to the inlet pipe. Have take off that side panel for access. I need to measure the pressure to discover whether I need to call my plumber to upgrade the piping down at the gas meter. The spec on the data sticker says 4.5 to 10.5 IWC ( Inches of water? ). Actually, the intake manometer port on this particular valve has been left out . Bet Hayward saved 50 cents on that.

So: How to connect a manometer? There is a sediment trap at the inlet, made of nominal 1 inch galvanized, with a cap at the bottom. I'm going to try to find some sort of adapter. If nothing found, I'll get a 1 inch cap, and drill & tap it for the manometer port.

 

[JamesW]

Picture of the gas valve?

Is this the test port?

 

[jerryk1234]

And a brass 1 inch NPT cap is on order. Also a 1/8 inch hose barb. Together, they will make a complete manometer adapter
for the sediment trap.

 

[jerryk1234]

Picture of the gas valve?

Is this the test port?
View attachment 622939

 

[jerryk1234]

Picture of the gas valve?

Is this the test port?
View attachment 622939

Nah, that's the *old* valve. Which does have a port. The new, and I guess, cheaper, gas valve has no port. There's a feature on the casting where the port SHOULD be, but it is not drilled & tapped. Here's the valve in the heater I just received.

Now, I thought of just swapping in the old valve - with its testing port - but I decided it was less work to make a port for the sediment trap. Also less risk of voiding the warranty. I found the datasheet of this new valve and there is SUPPOSED to be a testing port next to the input pipe. There is a depression in the casting where that port should be. But it is not drilled.

 

[JamesW]

 

[JamesW]

Can you show the In port?